And one POW who could take the stand as a leading witness for the prosecution in the case of man (Allied POWs) vs. man (Japanese prison guards) is Louis Zamperini, former Olympian and U.S. Air Corps bombardier.
Unbroken, by Laura Hillenbrand, masterfully tells the compelling and uplifting story of Louis Zamperini, tracing his troubled childhood to his triumphant track career, then focusing on his miraculous survival of 46 grueling days on a raft in the Pacific and his two plus years of torture and starvation as a prisoner of the inhumane Japanese, to his reunion with his family, and his troubled resumption of civilian life.
As the subtitle of the book says, Unbroken is a "story of survival, resilience, and redemption."
Beatings. Psychological torture. Meager rations. Filthy conditions. Forced labor. How Zamperini — and 1000s of POWs like him — were able to endure and in many cases even rise above the despicable, deplorable, brutal conditions of their imprisonment is beyond my comprehension.
Of the Axis powers that brought so much death and destruction to the world, the Japanese were demonstrably the most brutal in their treatment of POWs. Hillenbrand writes that it is estimated that only one percent of American POWs held by the Nazis and Italians died, while 37 percent held by the Japanese died . Those who survived the Japanese camps were mere skeletons — physically and psychologically — of their former selves.
The Pacific POWs who went home in 1945 were torn-down men. They had an intimate understanding of man's vast capacity to experience suffering, as well as his equally vast capacity, and hungry willingness, to inflict it. They carried unspeakable memories of torture and humiliation, and an acute sense of vulnerability that attended the knowledge of how readily they could be disarmed and dehumanized. Many felt lonely and isolated, having endured abuses that ordinary people couldn't understand. Their dignity had been obliterated, replaced with a pervasive sense of shame and worthlessness. 
The contrast to how the Americans treated Japanese POWs was immense. Hillenbrand writes of a post-war movement in Joetsu, location of the prison camp where Zamperini spent much of the war, to build a memorial to the POWs. One of the chief proponents of the memorial was Shoichi Ishizuka, who had been a POW held by the Americans. Ishizuka was "treated so kindly that he referred to the experience as 'lucky prison life.' When he learned what his Allied counterparts had endured in his own village, he was horrified" .
Hopefully Ishizuka was equally horrified by his imperialist nation's war on humanity, not just their mistreatment of POWs. The Axis powers brought untold death and destruction to the world, and though we often hear of Hitler's genocides, we are mistaken if we believe that the Japanese weren't Hitler's equal.
According to historian Chalmers Johnson:
It may be pointless to try to establish which World War Two Axis aggressor, Germany or Japan, was the more brutal to the peoples it victimised. The Germans killed six million Jews and 20 million Russians (i.e. Soviet citizens); the Japanese slaughtered as many as 30 million Filipinos, Malays, Vietnamese, Cambodians, Indonesians and Burmese, at least 23 million of them ethnic Chinese. Both nations looted the countries they conquered on a monumental scale, though Japan plundered more, over a longer period, than the Nazis. Both conquerors enslaved millions and exploited them as forced labourers—and, in the case of the Japanese, as (forced) prostitutes for front-line troops. If you were a Nazi prisoner of war from Britain, America, Australia, New Zealand or Canada (but not the Soviet Union) you faced a 4% chance of not surviving the war; (by comparison) the death rate for Allied POWs held by the Japanese was nearly 30%. [ref]
What the Japanese weren't prepared for was the Atom bomb. There has been a lot of debate over whether the United States should have dropped the Atom bomb on Hiroshima and Nagasaki. Although innocent life was lost, I have no doubt that it was the right decision. Clearly, many more thousands, perhaps hundreds of thousands of Allied lives would have been lost in an invasion of Japan. In all likelihood, all POWs held by the Japanese would have been executed as the ground war progressed, which was Japanese policy whenever the liberation of POWs was imminent.
After the defeat of Japan, and the liberation of the POWs held there, Hillenbrand writes about former POWs' train rides to Yokohama, and what was seen and thought by one of them as he passed Hiroshima:
From the top of Japan to the bottom, trains packed with POWs snaked toward Yokohama. Men pressed their faces to the windows to catch their first glimpse of what all of those B-29s had done. Once-grand cities were now flat, black stains, their only recognizable feature a gridwork of burned roads, passing nothing, leading nowhere.
At the first sight of the destruction of their enemies, the POWs cheered. But after the first city there was another, then another, city after city razed, the survivors drifting about like specters, picking through the rubble. The cheering died away. On Louie's train, the silence came as they passed through Tokyo. A week after Louie had left Omori, sixteen square miles of Tokyo, and tens of thousands of souls, had been immolated by B-29s.
A few of the trains slipped past Hiroshima. Virtually every POW believed that the destruction of this city had saved them from execution. John Falconer, a survivor of the Bataan Death March, looked out as Hiroshima neared. "First there were trees," he told historian Donald Knox. "Then the leaves were missing. As you got closer, branches were missing. Closer still, the trunks were gone and then, as you got in the middle, there was nothing. Nothing! It was beautiful. I realized this was what had ended the war. It meant we didn't have to go hungry any longer, or go without medical treatment. I was insensitive to anyone else's human needs and suffering. I know it's not right to say it was beautiful, because it really wasn't. But I believed the end probably justified the means." 
In her Acknowledgments at the end of Unbroken, Hillenbrand made this concluding and highly appropriate acknowledgement:
Finally, I wish to remember the millions of Allied servicemen and prisoners of war who lived the story of the Second World War. Many of these men never came home; many others returned bearing emotional and physical scars that would stay with them for the rest of their lives. I come away from this book with the deepest appreciation for what these men endured, and what they sacrificed, for the good of humanity. It is to them that this book is dedicated. 
Page references are from Unbroken, by Laura Hillenbrand, published by Random House, New York, 2010.
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